<template>
	<view>
		<my-search @click='gotoSearch'></my-search>
		<view class="scroll-view-container">
			<!-- 左侧的滚动视图区域 -->
			<scroll-view scroll-y="true" class="left-scroll-view" :style="{height: wh+'px'}">
				<block v-for="(item,index) in cateList" :key="item.cat_id">
					<view :class="['left-scroll-view-item',index===active?'active':''] " @click="activeChange(index)">
						{{item.cat_name}}</view>
				</block>
			</scroll-view>
			<!-- 右侧的滚动视图区域 -->
			<scroll-view scroll-y="true" class="right-scroll-view" :style="{height: wh+'px'}" :scroll-top="scrollTop">
				<block class="cate-lv2" v-for="(item2,index2) in cateLevel2" :key="item2.cat_id">
					<!-- 二级分类的标题 -->
					<view class="cate-lv2-title">
						/{{item2.cat_name}}/
					</view>
					<!-- 当前二级分类的三级分类的列表 -->
					<view class="cate-lv3-list">
						<view class="cate-lv3-item" v-for="(item3,index3) in item2.children" :key="item3.cat_id"
							@click="gotoGoodsList(item3)">
							<image :src="item3.cat_icon.replace('dev','web')" alt="图片" mode=""></image>
							<text>{{item3.cat_name}}</text>
						</view>
					</view>
				</block>

			</scroll-view>
		</view>
	</view>
</template>

<script>
	import badgeMix from "@/mixins/tabbar-badge.js"
	export default {
		data() {
			return {
				// 当前设备屏幕的可用高度
				wh: 0,
				// 一级分类列表
				cateList: [],
				// 当前选中项
				active: 0,
				// 二级分类列表
				cateLevel2: [],
				scrollTop: 0
			};
		},
		onLoad() {
			// 获取当前设备信息
			const sysInfo = uni.getSystemInfoSync()
			console.log(sysInfo)
			this.wh = sysInfo.windowHeight
			this.wh = sysInfo.windowHeight - 50
			// 调用方法
			this.getCateList()
		},
		methods: {
			// 获取分类列表的数据
			async getCateList() {
				const {
					data: res
				} = await uni.$http.get('/api/public/v1/categories')
				if (res.meta.status !== 200) return uni.$showMsg()
				this.cateList = res.message

				// 为二级分类列表赋值
				this.cateLevel2 = res.message[0].children
			},

			// 将当前索引赋值给active
			activeChange(index) {
				this.active = index
				// 重新为二级分类列表赋值，将当前项里面的子项赋值给二级列表
				this.cateLevel2 = this.cateList[index].children
				// 将scrollTop重置为0，是其每次点击都会返回到页面顶部
				this.scrollTop = 1 - this.scrollTop
			},
			// 跳转到商品列表详情页面,这里的item是形参，表示传递过来的参数
			gotoGoodsList(item) {
				uni.navigateTo({
					url: '/subpkg/goods_list/goods_list?cid=' + item.cat_id
				})
			},
			gotoSearch() {
				// 编程时路由导航
				uni.navigateTo({
					url: '/subpkg/search/search'
				})
			}
		},
		// 对混入文件进行挂载
		mixins:[badgeMix]
	}
</script>

<style lang="scss">
	.scroll-view-container {
		display: flex;

		.left-scroll-view {
			width: 120px;

			.left-scroll-view-item {
				background-color: #f7f7f7;
				line-height: 60px;
				text-align: center;
				font-size: 12px;

				// &代表上一级选择器
				&.active {
					background-color: #fff;
					position: relative;

					&::before {
						content: '';
						display: block;
						position: absolute;
						width: 3px;
						height: 30px;
						background-color: #c00000;
						top: 50%;
						left: 0;
						transform: translateY(-50%);
					}
				}
			}
		}

		.right-scroll-view {
			.cate-lv2-title {
				font-size: 12px;
				font-weight: bold;
				text-align: center;
				padding: 30px 0;
			}

			.cate-lv3-list {
				display: flex;
				flex-wrap: wrap;

				.cate-lv3-item {
					display: flex;
					flex-direction: column;
					justify-content: center;
					align-items: center;
					width: 33.33%;
					margin-bottom: 10px;

					image {
						width: 60px;
						height: 60px;
					}

					text {
						font-size: 12px;
					}
				}
			}
		}
	}
</style>
